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Welcome
The Dawning of Our Next Dawn
The Sun Also Cycles
Solar Maximum
Don't Let The Sun Bug You
Solar Minimum
But Wait There's More
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Solar Minimum
Just because Solar Maximum has its own quirks doesn't mean that a lack of activity gets us off the hook. Solar Minimum is characterized by a period of very few if any sunspots. Scientists claim they can predict the next two solar cycles by analyzing the flowing activity of what is called the Solar "Conveyor Belt." The Solar Conveyor Belt is a massive circulating current of hot plasma within the Sun. It has two branches, north and south, each taking about 40 years to complete one circuit cycle. The circuit constantly moves material from the center of the sun, churning up magnetic fields from its core to the surface and revealing them as sun spots. NASA solar physicist David Hathaway reports that the top of the sun's Great Conveyor Belt has been running at record-high speeds for the past five years.
 There has been a record speed of the flow circuit and researchers believe the fast pace has important ramifications. When the Conveyor Belt is moving rapidly it sweeps downward lots of old magnetic fields on the sun's surface to the sun's center, eventually returning to the surface again. The speed-up was surprising on two levels. First, it coincided with the deepest Solar Minimum in nearly 100 years, contradicting models that say a fast-moving belt should boost sunspot production. The basic idea is that the belt sweeps up magnetic fields from the sun's surface and drags them down to the sun's inner dynamo. Instead of boosting sunspots, Hathaway believes that a fast-moving Conveyor Belt can instead suppress sunspots them "by counteracting magnetic diffusion at the sun's equator."
The second surprise has to do with the bottom of the Conveyor Belt. The Solar and Heliospheric Observatory (SOHO) can only clock the motions of the visible top layer. The bottom is hidden by ~200,000 kilometers of overlying plasma. Nevertheless, an estimate of its speed can be made by tracking sunspots. "Sunspots are supposedly rooted to the bottom of the belt," says Hathaway. "So the motion of sunspots tells us how fast the belt is moving down there."
Hathaway has compared 'that-plotted sunspot' speeds vs. time since 1996-and the results don't make sense. "While the top of the conveyor belt has been moving at record-high speed, the bottom seems to be moving at record-low speed. Another contradiction."
According to David Hathaway. "It"s off the bottom of the charts",he says. "This has important repercussions for future solar activity." This past August (2008), the sun created no visible spots. The last time that happened was in June 1913 and the solar cycle thus far has remained a dud.
Researchers really need a good look deep inside the sun. NASA's Solar Dynamics Observatory, launched in February 2010, will provide that when its instruments come online later this year. SDO is able to map the sun's interior using a technique called helioseismology. SOHO can do the same thing, but not well enough to trace the Great Conveyor Belt all the way around. SDO's advanced sensors might reveal the complete circuit.
Here is an update, 4/1/09, NASA announced that the sun has plunged into the deepest solar minimum in nearly a century. "Sunspots have all but vanished and consequently the sun has become very quiet. In 2008, the sun had no spots 73% of the time, a 95-year low. In 2009, sunspots are even more scarce, with the "spotless rate" jumping to 87%. We are currently experiencing a stretch of days uninterrupted by sunspots--and there's no end in sight." And the sun remains to be quiet as of June 2009.
Severe space weather article
http://science.nasa.gov/headlines
NASA Conveyor Belt article
http://www.spacedaily.com/reports
Daily record of solar flare activity
http://www.solarcycle24.com
Free space weather bulletins
http://www.spaceweather.com
If Solar Cycle 24 remains at the current minimum activity level for another one to three years by using this method of labeling, the next solar cycle, #25 will be anticipated to be a very mild cycle with few sunspots even during the years when a Solar Maximum period would normally occur. Such extended periods have occurred before in our earths history and were observed during a period called the Dalton Minimum. One of the things about the Dalton Minimum was that it started with a skipped solar "peak" cycle, which also coincided with a very long Solar Cycle 4 from 1784-1799. The longer our current calm period lasts before we see a true ramp up of Cycle 24, the greater chance that Cycle 24 will be a "Solar Minimum".
In 2003, the NASA Goddard Institute for Space Studies published a release that agrees with the accepted idea that long period trends in solar activity do affect our climate by changing the Total Solar Irradiance.
Dalton Minimum returns, pdf file may take a moment to open.
http://sesfoundation.org/dalton_minimum.pdf
In 2006, William Livingston and Matt Penn wrote a paper for the journal Science. The paper was rejected in peer review and was never published by Science. Livingston said he was OK with the rejection. The paper was published elsewhere, most recently in 2008 in the Arizona Daily Star titled as "Sunspot cycle more dud than flood". The authors predicted that this could not only be a Solar Minimum cycle, but the start of another extended down period in solar activity. Their paper was based on analysis of weakening sunspot intensity and said sunspots might vanish by 2015. And here's the kicker: The last long-term down period, 1645-1715, coincided with the "Little Ice Age", a period of bitter cold winters known as the Maunder Minimum. Frigid winters and cold summers during that period led to massive crop failures, famine and great numbers of deaths in Northern Europe. Tree ring data has revealed that another "Little Ice Age" occurred a few hundred years prior to the 1715 event so a regular cycle is beginning to appear. Livingston said their projections were based on observations of a trend in decreasingly powerful sunspots but reviewers felt it was merely a "statistical argument".
But doesn't science pride itself as being based on statistical evidence? Remember to keep in mind that science uses itself as its own yardstick. Unpopular findings historically have always been swept aside and very often later resurrected as strokes of genius.
There are more links related to this category and other hot topics as they
constantly surface. Just click on the "This Just In" button on the menu bar.
Mini Ice Age
http://en.wikipedia.org/wiki/Maunder
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